Lead (II) ion | 14280-50-3

• 物质功能分类: 无机化工 - 单质
• 分子结构分类: 无机化合物 - 均相金属化合物 - 均相后过渡金属化合物
• 英文名称: Lead (II) ion
• 英文别名: lead(2+)
• CAS: 14280-50-3
• 化学式: Pb+2
• 分子量: 207.0
• InChiKey: RVPVRDXYQKGNMQ-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -0.38
• 重原子数：
  1
• 可旋转键数：
  0
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.0
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  0

ADMET

代谢

铅通过吸入、口服和皮肤接触被吸收，然后主要分布到骨骼和红细胞中。在血液中，铅可能被发现与血清白蛋白或金属结合蛋白金属lothionein结合。有机铅通过细胞色素P-450酶代谢，而无机铅与δ-氨基酮酸脱氢酶形成复合物。铅主要通过尿液和粪便排出。

Lead is absorbed following inhalation, oral, and dermal exposure. It is then distributed mainly to the bones and red blood cells. In the blood lead may be found bound to serum albumin or the metal-binding protein metallothionein. Organic lead is metabolized by cytochrome P-450 enzymes, whereas inorganic lead forms complexes with delta-aminolevulinic acid dehydratase. Lead is excreted mainly in the urine and faeces. (L136)

来源:Toxin and Toxin Target Database (T3DB)

毒理性

• 毒性总结

铅模仿其他生物学上重要的金属，如锌、钙和铁，作为许多它们各自酶促反应的辅因子与之竞争。例如，铅已被证明能竞争性地抑制钙与钙调蛋白的结合，干扰神经递质的释放。它对NMDA受体和蛋白激酶C表现出类似的竞争性抑制，这损害了脑微血管的形成和功能，同时也改变了血脑屏障。铅还通过阻碍多巴胺合成的调节和阻止乙酰胆碱的诱发释放来影响神经系统。然而，其主要作用机制是通过抑制δ-氨基酮酸脱水酶，这是一种在血红素生物合成中至关重要的酶，而血红素是血红蛋白必需的辅因子。(T4, A20, A22, L136)

Lead mimics other biologically important metals, such as zinc, calcium, and iron, competing as cofactors for many of their respective enzymatic reactions. For example, lead has been shown to competitively inhibit calcium's binding of calmodulin, interferring with neurotransmitter release. It exhibits similar competitive inhibition at the NMDA receptor and protein kinase C, which impairs brain microvascular formation and function, as well as alters the blood-brain barrier. Lead also affects the nervous system by impairing regulation of dopamine synthesis and blocking evoked release of acetylcholine. However, it's main mechanism of action occurs by inhibiting delta-aminolevulinic acid dehydratase, an enzyme vital in the biosynthesis of heme, which is a necesssary cofactor of hemoglobin. (T4, A20, A22, L136)

来源:Toxin and Toxin Target Database (T3DB)

毒理性

• 致癌物分类

2B，可能对人类有致癌性。

2B, possibly carcinogenic to humans. (L135)

来源:Toxin and Toxin Target Database (T3DB)

毒理性

• 健康影响

铅是一种神经毒素，已知会导致大脑损伤和认知能力下降，特别是在儿童中。铅暴露可能导致肾病，以及如高血压和贫血等血液疾病。铅还表现出生殖毒性，可能导致流产和减少精子产生。

Lead is a neurotoxin and has been known to cause brain damage and reduced cognitive capacity, especially in children. Lead exposure can result in nephropathy, as well as blood disorders such as high blood pressure and anemia. Lead also exhibits reproductive toxicity and can results in miscarriages and reduced sperm production. (L21)

来源:Toxin and Toxin Target Database (T3DB)

毒理性

• 暴露途径

口服（L136）；吸入（L136）；皮肤给药（L136）

Oral (L136) ; inhalation (L136) ; dermal (L136)

来源:Toxin and Toxin Target Database (T3DB)

毒理性

• 症状

慢性铅中毒的症状包括认知能力下降、恶心、腹痛、易怒、失眠、嘴里有金属味、过度乏力或过度活跃、胸痛、头痛，在极端情况下还可能出现癫痫、昏迷和死亡。此外，还可能伴有胃肠道问题，如便秘、腹泻、呕吐、食欲不振、体重减轻，这些在急性中毒中较为常见。

Symptoms of chronic lead poisoning include reduced cognitive abilities, nausea, abdominal pain, irritability, insomnia, metal taste in the mouth, excess lethargy or hyperactivity, chest pain, headache and, in extreme cases, seizures, comas, and death. There are also associated gastrointestinal problems, such as constipation, diarrhea, vomiting, poor appetite, weight loss, which are common in acute poisoning. (A2, L21)

来源:Toxin and Toxin Target Database (T3DB)